My understanding is a large percentage of the 2009 WWDC attendees are at a WWDC for the first time (which also means a large percentage will have never been to Stump the Experts before).

Stump the Experts is a game show.  A competition between the developers in the audience and a group of Apple “Experts” on stage.  This is the 18th year, we’ve been doing it for awhile.

The point of the game is to stump the Experts.  If you do so you win a point for your side, a coveted Stump t-shirt, as well as other prizes.  There are a few ways of doing so:

1. 1.Ask the Experts a question.  To do so, write your Apple development or trivia question on a 3x5 card along with your name and company and place the card in the box on stage (there are piles of 3x5 cards and pens on stage).  You need to know the answer to your question, but don’t write it on the card.  If your question is selected, your name will be called at which point you should go to one of the microphones in the room.
   

2. 2.Answer a question from the Experts.  The Experts have prepared a few questions for the audience which will be in the slides.  If you’d like to answer a question, come to a microphone and wait until you’re called upon.
   

3. 3.Identify some music.  Shortly after the Apple Design Awards end, we put on a special CD of songs.  This year there are 9 songs.  If you can name the title and artist of any of the songs, you win.  If you’d like to identify music, come to a microphone.  Don’t cheat and use your favorite iPhone music recognition application - we’ll know if you do and that will be bad.
   

There are often (always?) disputes about what the score actually is.  This year so that everyone can know exactly what the score is at all times, Quinn has graciously coded up “Mobile eXcoriation”, which you can download and build for your iPhone here (note that it is not compatible with iPhone OS 3.0).

More Stump info on wikipedia here.

Any and all disputes will be resolved by your hosts, Fred Huxham and/or Mark Harlan.  Know this:  If we say you're wrong, you are.  Especially if you're right.  This is a game, not a democracy.  Don't get confused by things you've learned in your civics classes.  Rules subject to change continually.

Have fun.